# v0.5.0 Plan

### foreign-key
- [x] define FK, add props at field, `x-foreignKey: "targetCollectionName"`  
    ```JSON
    {
        "username": {
            "type" : "string",
        },
        "contactId": {
            "type" : "string",
            "x-foreignKey" : "contact" // target collection's name
        }
    }
    ```
- [x] REST API, to request data with foreign-key collection:  
    add field name as array into querystring "_join"
    example `/user?_join=["contact"]_select=["contactNo"]&`